Bronchiectasis and nontuberculous mycobacterial disease.

Over the last 30 years it has become increasingly clear that nontuberculous mycobacterial (NTM) lung infections and bronchiectasis are closely related disorders. Although incontrovertible proof is lacking, there is a growing consensus of opinion that NTM lung disease characterized by nodules and bronchiectasis (nodular/bronchiectatic NTM lung disease) may be a consequence of preexisting bronchiectasis that predisposes to NTM infection and disease. To use published diagnostic guidelines effectively, physicians must become familiar with the disease-causing potential of individual NTM species. Essentially all NTM patients have bronchiectasis, so optimal overall patient management requires successful therapeutic strategies for both NTM infection and bronchiectasis.